How to filter when dynamic index has no value

[ktpktr0]

I use the label in the docker metadata to build an index dynamically. When the label of some containers does not exist or the value is empty, I get two indexes at the same time. How can I solve this problem

Logstash configuration

output {
    elasticsearch {
        hosts => ["192.168.6.195:9200"]
        index => "%{[container][labels][service]}-%{+YYYY.MM.dd}"
    }
}

[leandrojmp (Leandro Pereira)]

You need to check if the field exists.

output {
    if [container][labels][service] {
        elasticsearch {
            hosts => ["192.168.6.195:9200"]
            index => "%{[container][labels][service]}-%{+YYYY.MM.dd}"
        }
    } else if {
        elasticsearch {
            hosts => ["192.168.6.195:9200"]
            index => "index-name-%{+YYYY.MM.dd}"
        }
    }
}

[ktpktr0]

I've tried the following two methods, but none of them worked

output {
    if [container][labels][service] != "" {
       elasticsearch {

filter {
     json {
       source => "message"
   }
       ruby {
          code => "
             hash = event.to_hash
             hash.each do |k,v|
                if v == nil
                    event.remove(k)
                 end
             end
             "
    }
}

output {
    elasticsearch {

[ktpktr0]

I solved the problem. Thank you very much for your help